1. Field of the Invention
The present invention relates generally to an electromagnetic valve unit, and more particularly to the electromagnetic valve unit which is applicable to a hydraulic pressure control apparatus of an automobile.
2. Description of the Prior Art
In a conventional hydraulic pressure control apparatus of an automobile, such as an anti-skid control apparatus for example, electromagnetic valves have been employed for controlling the hydraulic pressure. For instance, it has been proposed to employ an electromagnetic valve unit, in which a plurality of electromagnetic valves are divided into a portion for controlling the hydraulic pressure and a solenoid coil portion. Accordingly, solenoid coils of the electromagnetic valves can be electrically connected at a time.
As for the electromagnetic valve unit provided for the hydraulic pressure control apparatus, a valve unit has been proposed in Japanese Patent Laid-open publication No. 1-199075 for example, to utilize a printed circuit board, as shown in FIG. 4, wherein the reference numerals in the parentheses are the same as those used in the publication. According to the valve unit disclosed in the publication, in order to simplify a process for mounting a cap (16) on a valve unit (1), there is provided as one unit, a printed circuit board (14) which is capable of being mounted on every electric contacts (10, 11) of coils (6, 7) and which has a wiring pattern for electrically connecting coils (6, 7) with an external cable (28), and contact means (21) commonly wired with all the contacts of the wiring pattern, and that a plug contact (31) detachable with the cable (28) is fitted into the printed circuit board (14) to form a portion of the common contact means (21). In this electromagnetic valve unit, a plug connector (29) is fixed to the cap (16), so that the plug contact (31) is connected with the printed circuit board (14).
However, according to the valve unit described in the above publication, the printed circuit board has been employed, so that it is still expensive, and it is necessary to connect the connector terminal with the board, and a large number of parts are required. Especially, once the wiring pattern was set, it would not be easy to change the wiring connection. For instance, when a common valve unit is installed on hydraulic pressure control apparatuses of various styles, it is possible to apply its electromagnetic valve portion commonly, but it is necessary in most cases to modify its wiring portion, with its connector terminals arranged inversely at the right and left positions, for example. Therefore, the wiring pattern has to be changed in the valve unit described above, so that a new printed circuit board will have to be made.
As for the one having the connector terminal which has been built in a plastic outer frame member by insert molding for example, when it becomes necessary to provide the connector terminal positioned inversely, a new molding die for the outer frame member has to be made, so that its manufacturing cost will be extremely high. Furthermore, since the metallic connector terminal is molded in the plastic outer frame member, they can not be separated from each other when they are to be disposed, and therefore recycling of waste will be difficult in this case.